1. Field of the Invention
The present invention generally relates to golf balls, and more particularly, to a golf ball in which the spherical surface is divided into 12 regular pentagons and 20 regular triangles corresponding to the faces of an icosidodecahedron, and to a golf ball with more exterior beauty in which the dimples of the ball cover are arranged not to visibly be distinguished from a mold parting line resulting from a two-part and without dimple free areas which arise from escaping dimple arrangement near the mold parting line and other symmetrical axes. Further, the golf ball of the present invention provides the largest efficiency of a flying distance and an accurate, and consistent flying orbit by extending the flying time of the golf ball after maximizing a dynamic lift and minimizing an air resistance against the golf ball.
2. Description of the Prior Arts
In general, there are two factors to fly a golf ball. Firstly, there is the initial velocity of a golf club head when the golf ball is struck by the club head, and secondly, there is the action of the dimple and back spin of the ball. Therefore, the large flying distance is produced by a long flying time being caused by the dynamic lift by means of such dimple and back spin action. For the conventional golf ball, because of a mold parting line resulting from molding the golf ball cover and a number of symmetrical axes to balance the spherical surface of the ball, the various limits which following the non-distribution area of the dimple happen when the dimples are arranged, thusly, the golf balls didn't receive the maximum dynamic lift. Accordingly, it was difficult to fly the golf ball in the desired direction. The flying distance was also shortened.
Additionally, to obtain optimum aerodynamic properties and an excellent flying ability of the golf ball, there were attempts to vary the size and depth of the dimples and the geometric arrangement of dimples on the surface.
U.S. Pat. No. 4,560,168 describes a golf ball in which the spherical surface of the ball is subdivided into twenty spherical surface triangles corresponding to the face numbers of a regular icosahedron, the respective spherical surface triangles are subdivided into four small triangles, and the dimples are arranged not to intersect with some sides of the central triangles. Accordingly, there are 6 symmetrical axes which don't intersect with a plurality of dimples formed on the spherical surface and any other dimples.
Alternatively, U.S. Pat. No. 4,142,727 describes a golf ball in which the spherical surface of the ball is subdivided into twelve areas corresponding to the faces of a regular dodecahedron. The surface includes 12 to 30 rectangular bald patches or dimple-free areas. The patent also refers to dividing the surface of the ball into areas corresponding to an octahedron or an icosahedron. In each case, however, from 12 to 30 bald patches will be present.
The Republic of Korea patent Gazette No. 80-1003 describes a golf ball in which the non-distribution area of at least 20 to 30 dimples is symmetrically disposed on the spherical surface of the ball and said dimple non-distribution area includes spherical rectangular bald patches consisting of at least half width of mean diameter of said dimples and at least two-fold of mean surface area of said dimples.
In respect of the dimple arrangement of the golf ball concerning with said patent Gazettes, because of a mold parting line resulting from molding the golf ball cover and a number of dividing lines for uniformity of the golf ball, various problems occur when the dimples are arranged, and thusly, said dimple arrangement consists of the non-distribution area and the symmetrical axes of dimple-free areas. This causes the golf ball not to be lifted at maximum when the golf ball is flying. Accordingly, it is a drawback that the flying distance of the golf ball is shortened.